Muscle exercising can be accomplished in many different ways including by a stationary individual or by an individual generally moving about. A very large selection of devices exists that provide for exercising of muscles, including without limitation, devices based on dead weights and devices based on active weights. Some of the simpler dead weight devices comprise dumbbells, typically composed of a short bar with large heavy balls or disks at opposing ends of the short bar, the short bar typically held with one hand, and barbells which are generally similar but composed of a longer bar meant to be held with two hands. The main common drawbacks of these devices are the amount of time and energy needed for a successful productive workout and the danger of cramping of the muscles. In particular, training with dumbbells and/or barbells places a high requirement on the endurance of the user, since measurable success requires a significantly long period of repetitive use.
Muscle stimulation by vibration is thought to exercise muscles by invoking a muscle's natural involuntary reflexive, or stretch, response, by imparting a sudden increase in load on the muscle over a predefined time period and over a predetermined amplitude. Such devices are commercially available, typically as whole body vibration platforms. However, such a platform does not allow for exercise of specific muscles.
U.S. Pat. No. 5,868,653, issued Feb. 9, 1999 to Klasen, the entire contents of which are incorporated herein by reference, is addressed to a vibrating barbell which includes a substantially tubular shaped barbell bar enclosing a device which causes the barbell bar to vibrate, comprising weights attached to each end of the barbell bar and a damping material interposed between the barbell bar and the weights. It is believed that the vibrations stimulate the nerves that coordinate the sequence of movement, and thus a more marked hypertrophy of the muscles used in lifting the device is noted with a reduced tendency to develop cramps. Disadvantageously, the majority of the benefit of the device remains solely a function of lifting the vibrating barbell, and is typically a function of the amount of repetition and continuous increase in the weight level being lifted. Further disadvantageously, the vibration rate and amplitude is not adjustable.
There is thus a long felt need for a device allowing for variable vibration speed and amplitude, which can be applied to specific muscles, or muscle groups.